Shearing mechanisms



Dec. 6, 1966 w. J. RICHMOND SHEARING MECHANISMS Z5 Sheets-Sheet 1 Filed May 26, 1964 INYENTOR WILLIAM J. RICHMOND HIS ATTORNEY Dec. 6, 1966 w, J, c o 3,289,518

SHEARING MECHANISMS Filed May 26, 1964 (5 Sheets-$heet 2 INVENTQR WILLIAM J. RICHMOND 17% cz- WW2:

HIS ATTORNEY 1386- 1966 w. J. RICHMOND SHEARING MECHANISMS 5 SheetsSheet 5 Filed M y 26, 1964 IMVELMTOE WILLIAM J. RICHMOND H 5 ATTORNEY United States Patent Ofiice 3,289,518 Patented Dec. 6, 1966 3,289,518 SHEARING MECHANISMS William James Richmond, Sheffield, England, asslgnor to Davy and United Engineering Company Limited, Yorkshire, England Filed May 26, 1964, Ser. No. 370,198 Claims priority, application Great Britain, May 28, 1963, 21,27 6/ 63 1 Claim. (Cl. 83-664) This invention relates to rotary drum shears. Previously, the drums carrying the cutting blades of rotary drum shears have been either rotatably mounted in bearings located directly into one piece housings arranged one on each side of the drums and suitably tied together, or, in an alternative arrangement, the bearings are located in chocks in windows in the one piece housings.

With such arrangements, when the drums have to be removed it is necessary, in the first case to remove the ties and separate the housings, and in the second case to remove keeper plates retaining the chocks in one housing Window, and pass the drums horizontally out through the window.

The present invention provides a shear comprising a pair of housings between which upper and lower co-operating blade carrying drums are rotatably mounted, each housing being formed in two parts, and means for detachably securing together the housing parts, such that when the upper housing parts are removed, the lower drum may be removed vertically.

In a preferred form the invention provides a shear comprising a pair of fixed spaced apart U-sectioned frames in which are supported lower chocks, between which a lower blade carrying drum is rotatably mounted, a pair of T-sectioned members between which an upper blade carrying drum is rotatably mounted, and means for prestressing the T-sectioned members to the U-sectioned frames respectively, such that the T-sectioned members may be removed vertically carrying the upper drum, and thereafter the lower drum and checks may be removed vertically from the frames.

The following description relates to the accompanying drawings which show, by way of example, a rotary scrap shear in accordance with the invention.

Of the drawings:

FIGURE 1 is a part-sectional side elevation of the shear,

FIGURE 2 is a section on the line 11-11 of FIGURE 1,

FIGURE 3 shows a modification to the drum driving means, and FIGURE 4 is a section on the line IVIV in FIGURE 3.

Referring to the drawings, drums 12 and 14, carrying blades 16, are secured to shafts 36 which are rotatably supported in lower and upper bearings 18 and 20 respectively. The bearings 18 are carried in chocks 22 which are supported between limbs 26, 28 of U-sectioned frames 27 forming the lower parts of fixed, spaced apart housings 29. The bearings 20 for the upper shaft 36 are directly mounted in T shaped chocks 30 which form the upper portions of the housings and which are pre-stressed to the limbs 26, 28 of the U section frames by bolts 32 and nuts 34. The bolts pass through bores in the members 30 and the limbs 22, 28.

The shafts 36, supporting the drums 12 and 14, carry intermeshing gears 38 and 40; the lower gear 40 also meshes with a drive pinion 42 in a pinion housing 43. The pinion 42 is driven by an electric motor, not shown. It will be seen that the drive is such that the drums are rotated at the same speed in opposite directions. At the other ends of the shafts 36, axial thrust bearing assemblies 44, 46 are provided, and selection of suitably dimensioned packing pieces 48 during assembly, facilitates the axial alignment of the drums 12 and 14 and so of the co-operating blades.

The housings 29 at each side of the drums are tied together by top and bottom bridging members 50 and 52 respectively.

Horizontal base parts 54 of the U section frames 27 are secured to a base member 56 by means, not shown.

A feed chute 58 conveys the material to be out to pass between the drums 12, 14, and a stop plate (not shown) supported at the lower end of an arm 60, pivotally supported at its upper end at 62, stops the passage of the material until the co-operating knives cut it, and the severed portion falls on a disposal chute 64. A further section of the material then passes between the drums and contacts the stop plate and the operation continues as described.

Lugs 65 about which a lifting sling may be passed, are provided on the top portions of the housing.

A gear cover 66 is also provided and this is secured to the adjacent housing by means (not shown).

When it is desired to remove the drums from the housings for maintenance work, the arm 60 is lifted away, the upper nuts 34 are removed, and the top portions 30 of the housings carrying the drum 14 are lifted up. The chocks 22 carrying the drum 12 can then also be removed vertically upwards from the U-sectioned frames 27.

It will be seen that with the arrangement shown, removal of the drums is greatly facilitated by the two-part housings, and the operation does not involve the use of a porter bar or other special provisions as required by conventional rotary drum shears when the drums are removed through windows in the housings.

The prestressing together of the two parts of each housing part also permits the use of a lighter housing for a given load carrying capacity.

In an alternative drive arrangement, the drums 12 and 14 are driven by universal spindles extending from a pinion stand located adjacent the shear housings. In this case, the gears 38 and 40, and the pinion 42 are not required. As shown in FIGURES 3 and 4, one of the gears 38, 40 may include means to adjust the gear circumferentially relative to the drive so that the required clearance between the blades 16 may be selected. In the drawings the gear 38 is mounted upon a sleeve 66 which is keyed to the drum shaft 68 by a key 70 and which has a work-wheel 72 integral therewith. The wormwheel engages with a worm 74 pivotally mounted by a shaft 76 between two lugs 78 secured to the gear 38. A square extension 80 of the shaft 76 allows the worm to be rotated by a spanner or the like so that the relative circumferential positions of the gear 38 and the blade 16 be suitably adjusted. In this way the optimum clearance between the blades 16 on each drum may be selected.

I claim:

A rotary drum shear comprising, in combination, two spaced-apart housings, upper and lower blade-carrying drums rotatably mounted between said housings, and

drive means coupled to said drums for rotating said drums in said housings, each said housing comprising separate upper and lower parts, said lower housing parts being of U-sections and carrying chocks rotatably mounting said lower drum between them, and said upper housing parts directly containing the bearings for the upper drum to form a unitary structure rotatably housing said upper drum and detachable as a whole with said upper drum from said lower housing parts to provide access to said lower drum for vertical removal thereof, and bolt means for each housing interconnecting said upper and lower parts thereof to prestress them in a direction opposing the shearing force.

References Cited by the Examiner UNITED STATES PATENTS FOREIGN PATENTS 7/ 1884 Germany.

WILLIAM W. DYER, JR., Primary Examiner.

L. VLACHOS, L. TAYLOR, Assistant Examiners, 

